This is an older review, and my opinion of this ink now is mostly negative, though I will admit that I haven’t traded the bottle and do still use it, but only with fine nibs. It’s an interesting concept and message, but the end result and usability of the ink is very limited.

Oddly enough it’s better behaved on copy paper:

Here’s a drip test:

And a full soak test:

I can’t tell you exactly how long it soaked, but it was probably 10-30 minutes. Washing away the yellow component of the ink really doesn’t take long to do.

Here’s my review of Diamine Beau Blue, an ink which I’d not given a fair chance and had already made up my mind to hate. But fortunately those feelings changed when I saw that icy blue goodness being laid down on Rhodia. And also, as you might notice, I’ve made up a completely superfluous term to go along with my reviews to describe a VERY desirable (for me) trait of inks that I call…

Grotto…

And onto the new term: Grotto.

I first noticed this trait in Herbin inks. In fact, if you look at some of my previous reviews I make several references to the “‘Herbin’ look”. It’s the beautiful darker-on-the-edges look that many J. Herbin inks can achieve when they dry on quality paper, and is especially prominent in nibs that are wet, bold, or flexy. I’d never had a name for it, but when reviewing this ink I found this particular quality so striking that I felt I had to name it.

To me it is a very “wet” look, like coffee that’s dried on non-absorbent paper. But I couldn’t call it “wetness” because people would think it just never dries (and what I call a “wet” look may very well trigger something completely different when someone else see’s it). So I ran with the word “wet” without actually using it, and after some thinking I decided I shall call this ink characteristic—at least within the context of future reviews—”grotto”. Grottos are mysterious, often beautiful places that might be harboring secrets. Their walls are often wet, and the water that might come from a natural spring and form a pool in them is clear and cool, straight from nature.

So now that I’ve gotten all the poetic junk out of the way, that’s “grotto”. This ink has great grotto. Not that I expect anyone else to pick up the word (though I’ll be perfectly happy if they do); it’s just a word to describe something I’ve been trying to describe for a long time.

This has become one of my favorite dark blue inks. Sei-Boku, along with its dark black sibling, Kiwa-Guro, is a fountain pen-safe pigmented ink. The vast majority of fountain pen inks derive their beautiful hues from dyes rather than pigments, as pigments tend to clog the small channels of fountain pen feeds. And while I’m unsure of if this ink gets its color from only pigment or a mix of pigment and dyes (I’m guess the latter), I can attest that this ink ran through the test pens perfectly fine and without any trouble. And while the manufacturer recommends flushing your pen between fills of this ink, that’s a pretty good ink hygiene habit to get into anyways.

On the page this ink also has a very prominent red/pink sheen, which I’ve found is a common color of sheen for blue inks.

And the one big plus for me with this ink? Here’s what it looks like on cheapo copy paper:

Look at that shading! The best part? It retains its fantastic sheen on copy paper as well! There is only one other ink I can think of that don’t feather and shade heavily and retain sheen: J. Herbin Rouge Hematite 1670. But as for blue inks that share this great behavior? In my experience, only Noodler’s Bad Blue Heron and Rohrer and Klingner’s Salix (an iron gall ink).